1. Field of the Invention
The present invention relates to an electric parking brake actuator, and more particularly to an electric parking brake actuator which is capable of measuring a tension of a cable.
2. Description of Related Art
In a conventional electric parking brake actuator having a cable-tension measuring device, a cable is cut into two segments and connected with a spring in series way. The compression of the spring can determine and calculate a tension of the cable. However, an extra balancer has to be mounted to balance the cut cable and this is inconvenient.
The tension of the cable is also measured by a feedback current of a motor. The big feedback current represents the big tension of the cable. However, the feedback current is easily interfered by other signal to cause an error of measurement.
To overcome the shortcomings, the present invention tends to provide an electric parking brake actuator to obviate the aforementioned problems.